The invention relates to a device and a process for heating an object made of thermoplastic material such as, for example, a glass or glass-ceramic plate, along a predetermined zone, for example, along the entire rim area of a glass plate.
For the heating of a glass plate on its rim area, e.g., in order to raise the edges of the glass plate, it was common practice heretofore to hold the plate over a rectangular ring of stationary burners until the rim area of the plate had reached a suitable temperature.
The purpose of the present invention is to provide a process and a device for heating an object made of thermoplastic material along an arbitrary zone quickly, exactly and above all homogeneously to a desired temperature.
The essential feature of the invention is that the burners are not arranged in a stationary manner relative to the object to be heated, but rather are arranged in series and moved over the zone to be heated. This arrangement results in a great deal of diversity with respect to the shape of the zone to be heated and the nature of the heating, i.e., homogeneous, without places with different temperatures.